1. Technical Field
The present invention relates to an electro-optical device including an organic EL (electro luminescent) element, a liquid crystal and the like and a method for driving the electro-optical device, and an electronic apparatus.
2. Related Art
In the past, there has been provided an electro-optical device including an organic EL element as an electro-optical element. The electro-optical device includes various driving circuits for supplying a predetermined current or voltage to the organic EL element and the like. Such a driving circuit may include, in addition to the organic EL element, for example, a capacitive element connected in parallel with the organic EL element. In this case, data potential is given to a positive electrode of the organic EL element and one electrode of the capacitive element, and a reference potential is given to a negative electrode of the organic EL element and the other electrode of the capacitive element. According to such configuration, electric charge accumulated in the capacitive element based on the data potential is given to the organic EL element, thereby enabling a stable driving of the organic EL element.
An example of such an electro-optical device is disclosed in JP-A-2000-122608.
In the electro-optical device described above, in order to obtain a sufficient amount of luminescence (time integral value of luminescence) of the organic EL element, a charge amount accumulated in the capacitive element needs to be large; thus, the capacitive element needs to be very large in capacity. However, because an area physically permitted for arranging each driving circuit may be limited, the capacitive element having such a large capacity is difficult to be achieved in the first place.
The present applicant already has proposed a technique disclosed in U.S. Patent Application Publication No. 2009/0195534, in which a capacitive element included in each of a plurality of driving circuits (unit circuits) is used for driving one organic EL element. For example, assuming that the driving circuits are arrayed in one row, the number of the driving circuits is N (therefore, N capacitive elements and N organic EL elements are provided correspondingly). When a certain organic EL element is driven, first, the N capacitive elements included in all the driving circuits are simultaneously charged in accordance with the data potential corresponding to the relevant organic EL element, and subsequently, the N capacitive elements are simultaneously discharged (i.e., current is supplied) for the relevant organic EL element.
With the above-described configuration, the above mentioned difficulties can be reduced.
However, further improvement is desired in such a technique.
That is, in the above example of JP-A-2000-122608, an example is disclosed in which a switching element is arranged between the capacitive element and the organic EL element in each driving circuit. The switching element is an element which is first (i.e., in the simultaneous charging) held in a non-conducted state, and subsequently (i.e., in the simultaneous discharging) in a conducted state to suitably charge the capacitive element and supply current to the organic EL element by the discharge therefrom.
However, the switching element is basically provided to each of the driving circuits. Accordingly, it may be difficult to have the quality and characteristics in a predetermined range for all the driving circuits. If undesired variations are generated in the quality, characteristics and the like, a performance of the entire electro-optical device (e.g., maintaining and improving image quality) may be affected. Moreover, the necessity for providing the switching element itself may reduce the yield in the first place.